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Internal adaptation of restorations to the cavity wall is one of the important topics in clinical dentistry. The purpose of this study was to investigate the possibility to utilize the non-invasive tomographic imaging system for teaching the importance of cavity adaptation at dental school pre-clinical training. Swept-source optical coherence tomography (SS-OCT) was used for detection of marginal and internal defects in the composite resin restorations as an educational device. Class 1 and Class 2 composite restorations to melamine resin molar tooth were assigned to the students and prepared during the skill test, and SS-OCT imaging was performed to evaluate students' works. SS-OCT could detect the internal gaps and voids within the restorations in tomography images synthesized based on the backscatter signal from within the restoration. It is suggested that the SS-OCT is promising diagnostic modality, as well as educational imaging device for the detection of internal gaps in adhesive restorations.  相似文献   
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Background

Renal anemia complicated with chronic kidney disease is usually treated with erythropoiesis-stimulating agents (ESAs). However, few studies have compared the early response of hemoglobin (Hb) to different kinds of ESAs.

Methods

The effects of three types of ESAs—epoetin alfa or beta (EPO), darbepoetin alfa (DPO), and epoetin beta pegol (EPObp)—on renal anemia were followed in 416 pre-dialysis chronic kidney disease (CKD) patients. After the initial 12-week administration of ESAs, ΔHb/ESA dose/kg was calculated as an index of efficacy of each ESA. Furthermore, independent variables associated with ΔHb/ESA dose/kg (dependent variable) were determined using multiple linear regression analysis. The ten independent variables selected for analysis were: presence of diabetic nephropathy, estimated glomerular filtration rate (eGFR), Hb, albumin, iron (Fe), transferrin saturation (TSAT), ferritin, phosphate (P), intact parathyroid hormone (iPTH), and C-reactive protein.

Results

The efficacy of DPO and EPObp were similar and higher than EPO. TSAT was most strongly correlated with ΔHb/EPO dose/kg in all three types of ESAs. Other significant independent factors were Hb, albumin, P, iPTH, and diabetic nephropathy in the EPO group, eGFR in the DPO group, and Fe in the EPObp group. The adjusted coefficient of determination (R 2) ranged from 0.415 to 0.520 in the three ESA groups.

Conclusions

The study results suggest that TSAT is the best predictor of the initial 12-week responsiveness to ESA, irrespective of the type. Variables not investigated in this study also affect responsiveness to ESA in Japanese pre-dialysis CKD patients.
  相似文献   
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Background

The prevention of relapse and infection complications during remission maintenance therapy is required to improve the prognosis of patients with microscopic polyangiitis (MPA) showing rapidly progressive glomerulonephritis (RPGN). The clinicopathological characteristics of patients with ANCA-positive MPA were examined to determine the risk factors for relapse or infectious complications after remission induction therapy.

Patients and methods

The study population consisted of 52 patients diagnosed as ANCA-positive MPA showing RPGN from 2002 to 2012, after publication of the Japanese guideline for RPGN. The clinicopathological findings were examined between the presence and absence of relapse or infectious complications.

Results

The value of vasculitis damage index (VDI) was high for the relapse group and VDI value was identified as the leading factor associated with relapse [hazard ratio (HR) 3.36, 95 % confidence interval (CI) 1.58–7.12, P < 0.01]. On the other hand, the values of Birmingham Vasculitis Activity Score, clinical grade category of RPGN at diagnosis, and VDI at remission were high in the infectious group. Furthermore, clinical grade category of RPGN was the leading factor associated with infectious complications (HR 5.30, 95 % CI 1.41–19.9, P = 0.01).

Conclusion

The disease activity at diagnosis and severity of organ damage at remission were associated with relapse and infectious complications during remission maintenance therapy and infectious complication affected kidney survival and all-cause mortality in patients with ANCA-positive MPA exhibiting RPGN.
  相似文献   
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Relationships between insulin release and taste   总被引:1,自引:0,他引:1  
Tasting sweet food elicits insulin release prior to increasing plasma glucose levels, known as cephalic phase insulin release (CPIR). The characteristic of CPIR is that plasma insulin secretion occurs before the rise of the plasma glucose level. In this experiment, we examined whether taste stimuli placed on the tongue could induce CPIR. We used female Wistar rats and five basic taste stimuli: sucrose (sweet), sodium chloride (salty), HCl (sour), quinine (bitter) or monosodium glutamate (umami). Rats reliably exhibited CPIR to sucrose. Sodium chloride, HCl, quinine, or monosodium glutamate did not elicit CPIR. The non-nutritive sweetener saccharine elicited CPIR. However, starch, which is nutritive but non-sweet, did not elicit CPIR although rats showed a strong preference for starch which is a source of glucose. In addition, we studied whether CPIR was related to taste receptor cell activity. We carried out the experiment in rats with bilaterally cut chorda tympani nerves, one of the gustatory nerves. After sectioning, CPIR was not observed for sweet stimulation. From these results, we conclude that sweetness information conducted by thistaste nerve provides essential information for eliciting CPIR.  相似文献   
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Macrolide antibiotics are widely used at clinical sites. Clarithromycin (CAM), a 14-membered macrolide antibiotic, was reported to gelate under acidic conditions. Gelation allows oral administration of acid-sensitive CAM without enteric coating by hindering the penetration of gastric fluid into CAM tablets. However, it is unknown whether this phenomenon occurs in other macrolide antibiotics. In this study, we examined the gelation ability of 3 widely used macrolide antibiotics, roxithromycin (RXM), erythromycin A, and azithromycin. The results indicated that not only CAM but also RXM gelated under acidic conditions. Erythromycin A and azithromycin did not gelate under the same conditions. Gelation of RXM delayed the disintegration of the tablet and release of RXM from the tablet. Disintegration and release were also delayed in commercial RXM tablets containing disintegrants. This study showed that 2 of the 4 macrolides gelated, which affects tablet disintegration and dissolution and suggests that this phenomenon might also occur in other macrolides.  相似文献   
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